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Question

What is the molarity of a solution consisting of 324 g of Yb₂(SO₄)₃ in 2.50 L of solution

Answer 1

Hello, Raphael,

Molarity is defined as moles per liter. We have 2.5 liters of solution, so we need to find the number of moles of Yb₂(SO₄)₃ contained in 324 g of the substance. Moles are calculated by dividing the mass by the molar mass of Yb₂(SO₄)₃ (g/mole). Add the atomic weights of each of the atoms in the compound. I get 634.3 g/mole, but check my math.

Moles Yb₂(SO₄)₃ = 324g/(634.3 g/mole) = 0.519 moles

Convert this into Molarity by dividing the moles by the volume.

0.519 moles/2.5 Liters = 0.208 moles/liter, or Molar

Bob

Answer 2

Molarity is moles/liters

Find the number of moles in 324 grams of the compound

324 g Yb₂(SO₄)₃ 1 mole

634.28 grams

0.51 moles /2.5 liters = 0.2 M

Molarity is 0.2